(18.V.95), An efficient combination of electrospray mass spectrometry (ES-MS), spectrophotometric and 'H-NMR titrations in solution is used to characterize the assembly of the segmental ligand 2-{ 6-[1-(3,S-dimethoxybenzyl)-azole] (L') with Zn" and 4f metal ions, Ln"'. Ligand L2 reacts with Zn(ClO,), in MeCN to give successively [Zn(L2),I2', where the metal ion is coordinated by the tridentate binding units of the ligands, and the double-helical head-to-head complex [Zn2(L2)2]4'. When L2 reacts with Ln(CIO,), (Ln = La, Eu, Lu), La"' only leads to a well-defined cylindrical CI-symmetrical homodinuciear head-to-tail complex [La2(L2),16' in solution, while chemical-exchange processes prevent the 'H-NMR characterization of [Eu2(L2)$', and Lu"' gives complicated mixtures of complexes. However, stoichiometric amounts of Ln"' (Ln = La, Ce, Pr, Nd, Sm, Eu, Tb, Y, Lu), Zn", and L2 in a 1 :I : 3 ratio lead to the selective formation of the C,-symmetrical heterodinuclear complexes [LnZn(L2)3]S+ under thermodynamic control. Detailed NOE studies show that the ligands are wrapped about the C, axis defined by the metal ions, and the separation of dipolar and contact contributions to the 'H-NMR paramagnetic shifts of the axial complexes [LnZn(L2)3]S+ (Ln = Ce, Pr, Nd, Sm, Eu) in MeCN establishes that Zn" occupies the pseudo-octahedral capping coordination site defined by the three bidentate binding units, while Ln"' lies in the resulting 'facial' pseudo-tricapped trigonal prismatic site produced by the three remaining tridentate units. Photophysical measurements show that [LnZn(L*),]'+ (Ln = Eu, Tb) are only weakly luminescent because of quenching processes associated with the C,-cylindrical structure of the complexes. The use of 3d metal ions to control and design isomerically pure 'facial' tricapped trigonal prismatic lanthanide building blocks is discussed together with the calculation of a new nephelauxetic parameter associated with heterocyclic N-atoms coordinated to Ln'".Introduction. - [7]. However, the recent development of selective self-assembly processes between segmental ligands and metal ions leading to programmed architectures [8] [9] has reached a point where it is now possible to tailor

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. Highly preorganized cryptands [5] and podands [6] have been used to control the coordination sphere around Ln"', but it was recently realized that less constrained ligands may also lead to well-defined lanthanide complexes. E.g., Lnr" ions react with linear heterocyclic oligotridentate ligands such as L3

The biotransformation of a mixture of resveratrol and pterostilbene was performed by the protein secretome of Botrytis cinerea. Several reaction conditions were tested to overcome solubility issues and to improve enzymatic activity. Using MeOH as co-solvent, a series of unusual methoxylated compounds was generated. The reaction was scaled-up and the resulting mixture purified by semi-preparative HPLC-PDA-ELSD-MS. Using this approach, 15 analogues were isolated in one step. Upon full characterization by NMR and HRMS analyses, eight of the compounds were new. The antibacterial activities of the isolated compounds were evaluated in vitro against the opportunistic pathogens, Pseudomonas aeruginosa and Staphylococcus aureus. The selectivity index (SI) was calculated based on cytotoxic assays performed against human liver carcinoma cells (HepG2) and human breast epithelial cell line (MCF10A). Some compounds revealed remarkable antibacterial activity against multidrug-resistant strains of S. aureus on the background of the moderate human cell line cytotoxicity.